INVESTIGADORES
VELASCO Ricardo Hugo
congresos y reuniones científicas
Título:
137Cs global fallout in Latin-American and Antarctic soils,
Autor/es:
MUNIZ, M.; CARDOSO, R.; FAGUNDES, B.; MEIGIKOS DOS ANJOS, R.; J. JURI AYUB; LOHAIZA F.; H. VELASCO; RIZZOTTO, M.
Lugar:
Sao Sebastiao
Reunión:
Congreso; XXXV Reunião de Trabalho sobre Física Nuclear no Brasil; 2012
Institución organizadora:
Sociedade Brasileira de Fisica
Resumen:
For
North hemisphere and European countries information
about the 137Cs content in soils due to global fallout
is very extensive; and the resulting patterns are well
known and understood. For Latin American soils the
information is more scarce and scattered. In the last years
with the beginning of the use of 137Cs to determine
soil redistribution rates, information about 137Cs soil
content in several experimental sites (reference sites)
can be found in the literature for some Latin American
countries; and it is now possible to expand our understanding
of how has been the 137Cs fallout in this region.
With this aim in mind a database of 137Cs areal activity
density was constructed. The database contains
more than 330 values of 137Cs for Latin America and
Antarctic regions. The database was elaborated using
bibliographic sources and personal data. When the effect
of the latitude is evaluated, a typical pattern is
found. The 137Cs soil content increases from Ecuador
and the Antarctic region to the middle latitudes. The
137Cs values for each range of latitude are lower than
that reported for the Northern hemisphere, but higher
than that estimated by UNSCEAR for the Southern
hemisphere. For the Latin American region, the 137Cs
areal activity density shows correlation with the annual
mean rainfall rate (Pearson coefficient 0.6). Although
this coefficient value is not large, taking into account the
large surface of land assessed, the effect of precipitation
should not be rejected. In order to assess the distribution
within these vast areas, the available data were
grouped according to geographical location and maps of
137Cs fallout and annual mean rainfall were constructed
and analyzed, focused in the like